That would be Jeronne Maymon's right knee. If it's healthy enough that he can play close to his normal level, the Vols (19-14) have a good chance to prevail on their home court at Thompson-Boling Arena. If not, the odds shift toward the visiting Blue Raiders (26-6).
Tennessee beat Savannah State 65-51 in first-round NIT action without Maymon in the post because the Tigers basically have no posts, instead going with four wings and a point guard. Conversely, Middle Tennessee plays two posts, and one of them happens to be the 2012 Sun Belt Conference Player of the Year.
The award-winner is Iowa State transfer Laron Dendy, a 6-foot-9, 230-pounder who leads MTSU in points (14.8 per game) and rebounds (7.0). His inside running mate, 6-foot-8, 230-pound J.T. Sulton, is no slouch. He averages 10.4 points and 5.4 rebounds per game.
Tennessee may be unable to contain Dendy and Sulton without Maymon, a 6-foot-7, 265-pound bruiser who averaged 12.6 points and 8.1 rebounds in the first 32 games before missing the Savannah State outing due to the knee injury.
Even if Maymon is cleared to face Middle Tennessee, he will be somewhat limited.
"He won't be 100 percent going out there," head coach Cuonzo Martin said. "If he can help us he'll help us but we have to make a decision and do what's best for Jeronne."
Although Maymon was tabbed second-team all-conference by the SEC coaches, Martin thinks his player was short-changed.
"You're talking about in my opinion a first-team all-league guy in Jeronne Maymon," the Vol coach said. "I'd take that to bat any day of the week. He's a guy that battles, a guy that rebounds at a high level ... defends. He does so many things."
Including lead. That's one of the under-appreciated aspects of Maymon's game.
"Even besides the points, it's (important) having Jeronne out there," sophomore wing Jordan McRae said. "He does a lot of talking and he's intense. Not having him out there hurts us a little bit."
Another under-appreciated aspect of Maymon's game is his skill as an interior passer.
"He's a guy that does a really good job of facilitating the offense as kind of a point forward-type guy," Martin said. "He can maneuver, go off the dribble and make plays for a big guy — pick and pop and attack the rim."
Maymon also is the Vols' best interior defender. Without him, Savannah State's Rashad Hassan burned Tennessee for 20 points and 14 rebounds last Monday night.
Noting that Maymon is "big and physical and a really good defender," Martin added: "You can't lose a guy like that and expect to be clicking on all cylinders. And you can't expect guys who haven't played a lot to step up and be Jeronne Maymon. It just doesn't happen."
Yet another Maymon benefit that often goes unnoticed is his work as a mentor to freshman post Jarnell Stokes. Maymon has contributed almost as much to Stokes' development as the coaching staff has.
"Jeronne has really been teaching Jarnell a lot about the game — how to approach the game, angles, so many different things," Martin said. "Now you don't have the luxury of having that guy right there."
Bottom line: Tennessee has won nine of its last 11 games but it may need Maymon in the lineup to continue its late-season surge.
"I think our team is playing really good ball," McRae said. "As soon as we get Jeronne back 100 percent, I think we'll be back to being a great team."
For what it's worth, McRae thinks Maymon will be in uniform Monday night.
"Jeronne is not the kind of player who's going to sit out too long, so I think he'll be back before you know it," McRae said. "He loves to compete. Especially with Coach Martin saying how good their (Blue Raiders') bigs are, I definitely think he'll be out there."
LOOKING AHEAD: The winner of the game between No. 1 seed Tennessee and No. 4 seed Middle Tennessee will play again Wednesday night at Thompson-Boling against the winner between No. 2 seed Miami and No. 6 seed Minnesota. Miami moved to 20-12 with a 66-50 first-round NIT defeat of Valparaiso. Minnesota, coached by former Kentucky head man Tubby Smith, improved to 20-14 by beating LaSalle 70-61 in Round 1.